What is an SSL certificate? [2025]

An SSL certificate ensures that the connection between your website and visitors is encrypted. All data that is sent via contact forms, logins or orders, for example, is made unreadable before it leaves the Internet. Without SSL, your website not only appears insecure, but can also be actively marked as “Not secure” in the browser.

What is the difference between SSL and TLS?

Originally, the encryption standard was called SSL (Secure Sockets Layer). Its modern successor is called TLS (Transport Layer Security) and is used practically everywhere today. In everyday life, however, almost everyone still refers to an “SSL certificate” – which always means the current TLS encryption.

Do you need SSL encryption?

Yes – by 2025, SSL encryption will be mandatory for every website, not just online stores. Without https, you risk warning messages in the browser, less trust from visitors and disadvantages with Google.

• Data protection: Forms, logins and personal data are transmitted in encrypted form.
• Trust: The lock symbol signals to visitors that they are on a reputable site.
• Law & GDPR: Anyone processing personal data should use a secure connection.
• Professionalism: “Not secure” notices in the browser look unprofessional and are a deterrent.

If you are planning your first website, the guide Create a website 2025 – Step-by-step guide will show you the entire path from domain and hosting to a secure https website.

How can I tell if a website uses SSL?

You can tell whether a website is secured with SSL or TLS in just a few seconds:

• https instead of http: In the address bar, https:// appears before the domain (e. g. https://bscwebdesign.at).
• Lock symbol: Most browsers show a lock or a security icon to the left of the URL.
• No warning messages: No message such as “Connection is not secure” or “This website is not trustworthy” appears.
• Certificate details: If you click on the lock, you can view further information about the certificate (issuer, validity, etc.).

Is SSL good for SEO?

Yes – Google prefers websites that are secured with https. SSL is not the sole ranking booster, but without an encrypted connection you have a clear disadvantage compared to secure websites.

• Ranking signal: Google has confirmed that https is a positive signal in the algorithm.
• Better user signals: Users are less likely to leave the site if the browser does not display any security warnings.
• Trust with clicks: In many browsers and tools, https is clearly highlighted – this increases the willingness to click.

Conclusion: SSL certificate as the basis for every modern website

Without SSL, your website looks outdated and insecure. With an activated certificate, you protect data, increase the trust of your visitors and at the same time meet minimum technical and legal standards.

• https and lock symbol immediately create trust.
• Browser warning messages are avoided.
• Google rates secure websites positively.
• SSL is included free of charge with many hosters – the only problem is usually setting it up.

Frequently asked questions about SSL certificates

What exactly does an SSL certificate do?

An SSL certificate encrypts the connection between the browser and server so that third parties cannot read data such as names, email addresses or passwords. It also confirms that the server really belongs to the domain that is displayed in the browser.

Do I also need SSL for a small website without a store?

Yes, because even on a seemingly simple website, personal data is often transferred – for example via contact forms, newsletter registrations or login areas. In addition, a “Not secure” notice looks dubious, even on a business card website.

Does an SSL certificate cost money?

Many hosters now offer free certificates (e.g. via Let’s Encrypt) directly in the package. For special requirements, larger companies or extended validation, paid certificates can be useful – but for most SMEs, a free SSL certificate is sufficient.

How long is an SSL certificate valid?

Most certificates are valid for a few months to a year and are then automatically renewed. It is important that the automatic renewal is set up correctly with the hoster or server – otherwise expired certificates and security warnings may occur.